Sökning: onr:"swepub:oai:DiVA.org:uu-485326" >
Zircon and monazite...
Zircon and monazite reveal late Cambrian/early Ordovician partial melting of the Central Seve Nappe Complex, Scandinavian Caledonides
-
- Barnes, Christopher J. (författare)
- Polish Acad Sci, Inst Geol Sci, Krakow, Poland.
-
- Bukala, Michal (författare)
- Polish Acad Sci, Inst Geol Sci, Krakow, Poland.
-
- Callegari, Riccardo (författare)
- Uppsala universitet,Mineralogi, petrologi och tektonik,AGH Univ Sci & Technol, Fac Geol Geophys & Environm Protect, Krakow, Poland.
-
visa fler...
-
- Walczak, Katarzyna (författare)
- AGH Univ Sci & Technol, Fac Geol Geophys & Environm Protect, Krakow, Poland.
-
- Kooijman, Ellen (författare)
- Naturhistoriska riksmuseet,Enheten för geovetenskap,Department of Geosciences Swedish Museum of Natural History Stockholm Sweden,Swedish Museum Nat Hist, Dept Geosci, Stockholm, Sweden.
-
- Kielman-Schmitt, Melanie, 1988- (författare)
- Naturhistoriska riksmuseet,Enheten för geovetenskap,Vegacenter,Swedish Museum Nat Hist, Dept Geosci, Stockholm, Sweden.
-
- Majka, Jaroslaw (författare)
- Uppsala universitet,Mineralogi, petrologi och tektonik,AGH Univ Sci & Technol, Fac Geol Geophys & Environm Protect, Krakow, Poland.
-
visa färre...
-
Polish Acad Sci, Inst Geol Sci, Krakow, Poland Mineralogi, petrologi och tektonik (creator_code:org_t)
- 2022-09-14
- 2022
- Engelska.
-
Ingår i: Contributions to Mineralogy and Petrology. - : Springer. - 0010-7999 .- 1432-0967. ; 177:9
- Relaterad länk:
-
https://doi.org/10.1...
-
visa fler...
-
https://uu.diva-port... (primary) (Raw object)
-
https://urn.kb.se/re...
-
https://doi.org/10.1...
-
https://urn.kb.se/re...
-
visa färre...
Abstract
Ämnesord
Stäng
- The Seve Nappe Complex (SNC) comprises continental rocks of Baltica that were subducted and exhumed during the Caledonian orogeny prior to collision with Laurentia. The tectonic history of the central SNC is investigated by applying in-situ zircon and monazite (Th-)U-Pb geochronology and trace element analysis to (ultra-)high pressure (UHP) paragneisses in the Avardo and Marsfjallet gneisses. Zircons in the Avardo Gneiss exposed at Sippmikk creek exhibit xenocrystic cores with metamorphic rims. Cores show typical igneous REE profiles and were affected by partial Pb-loss. The rims have flat HREE profiles and are interpreted to have crystallized at 482.5 +/- 3.7 Ma during biotite-dehydration melting and peritectic garnet growth. Monazites in the paragneiss are chemically homogeneous and record metamorphism at 420.6 +/- 2.0 Ma. In the Marsfjallet Gneiss exposed near Kittelfjall, monazites exhibit complex zoning with cores enveloped by mantles and rims. The cores are interpreted to have crystallized at 481.6 +/- 2.1 Ma, possibly during garnet resorption. The mantles and rims provide a dispersion of dates and are interpreted to have formed by melt-driven dissolution-reprecipitation of pre-existing monazites until 463.1 +/- 1.8 Ma. Depletion of Y, HREE, and U in the mantles and rims compared to the cores record peritectic garnet and zircon growth. Altogether, the Avardo and Marsfjallet gneisses show evidence of late Cambrian/early Ordovician partial melting (possibly in (U)HP conditions), Middle Ordovician (U)HP metamorphism, and late Silurian tectonism. These results indicate that the SNC underwent south-to-north oblique subduction in late Cambrian time, followed by progressive north-to-south exhumation to crustal levels prior to late Silurian continental collision.
Ämnesord
- NATURVETENSKAP -- Geovetenskap och miljövetenskap -- Geologi (hsv//swe)
- NATURAL SCIENCES -- Earth and Related Environmental Sciences -- Geology (hsv//eng)
- NATURVETENSKAP -- Geovetenskap och miljövetenskap -- Geokemi (hsv//swe)
- NATURAL SCIENCES -- Earth and Related Environmental Sciences -- Geochemistry (hsv//eng)
Nyckelord
- Caledonian orogeny
- Zircon U-Pb geochronology
- Monazite Th-U-Pb geochronology
- Partial melting
- Continental subduction
- The changing Earth
Publikations- och innehållstyp
- ref (ämneskategori)
- art (ämneskategori)
Hitta via bibliotek
Till lärosätets databas